So I've recently played around with Juju, and I see quite a bit of potential. But there are a few things I don't exactly understand. Most notably, I'm not sure of the purpose of the "bootstrapping instance" (aka "bootstrapping node" or machine “0”).

1 Answer
1

The bootstrap instance runs two critical pieces of the infrastructure: Zookeeper and the provisioning agent. Here is the architecture overview:

Right now this is actually a single point of failure.. though that will be solved in the near term by expanding the "bootstrap" service to 2 units either on demand, or in response to deploying a second machine. Luckily, Zookeeper is designed for high availability and the provision agent will use Zookeeper for coordination so its not a complex problem to solve, just one that needs to be solved before Juju is ready for real production usage.